Where to find startup ideas?

A lot of people what to create startups. Entrepreneurship is just in the blood for some folks. I have read about serial entrepreneurs. They make a business, get it going, make another, get it going, and BOOM! BOOM! BOOM! Hit after money-making hit. Occasionally, Hacker News will have an “Ask HN” where people talk about where to find startup ideas. I’ve put some suggestions from the most recent one here so that folks can find it if they’re looking without having to parse through a bunch of comments.